“This shift ... could have far-reaching implications for the global solar industry, especially vaulting China into the top ranks of countries pursuing solar R&D,” Stanford University said in its 2017 report on the solar industry.

These have been cheaper to produce than the more efficient mono-crystalline cells, which are made from single crystalline units.

The price of multi-crystalline cells has dropped to well below 50 cents per watt from $80 in 1980.

But prices are now converging as China scales up production of mono-crystalline cells.

Energy Trend, a consultancy, says the average price of a Chinese high-efficiency, multi-crystalline cell is now $0.225 per watt, compared to just $0.319 for high-efficiency, mono-crystalline cells.

“With poly-silicon products, we have seen the (development) ceiling. Now, we are ramping up investment of mono-solar,” said Xie Tian, director of quality management at LONGi Green Energy Technology. “Mono-crystalline can take more than 50 percent of the market,” he said, up from around a fifth today.

Analysts say demand for mono-crystalline panels is already strong.

“Many panel makers... can’t meet orders. Their bookings are full until next year,” said Jason Tsai of Energy Trend.

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NOT NEW, BUT BETTER

Mono-crystalline technology is not new, but because of its cost, has mainly been used in high-tech space products.

But its use is likely to increase as the cost differential narrows, meaning a higher efficiency can be had at a similar price.

Under the “Top Runner” program, pay-outs known as Feed-in-Tariffs will favor high-efficiency projects.

“It’s much easier to meet the requirements on mono, therefore it (the program) is accelerating investment in mono,” said Steve O‘Neil, CEO of REC Solar, a Singapore-based panel maker owned by Chinese state-owned ChemChina.

Germany’s Fraunhofer Institute for Solar Energy, a leader in solar development, said in July the record laboratory efficiency for mono-crystalline was 26.7 percent per cell, versus 21.9 percent for multi-crystalline.

While China is driving the shift into mono-crystalline, producers globally are adapting.

REC, for example, says it is starting to move into mono-crystallines after focusing largely on multi-crystalline cells.

“We’ve been looking into mono to further improve power output. In early July, we started production of a... mono solar panel specifically designed for Japan’s residential market,” O‘Neil said.